TY - JOUR T1 - STUDIES ON THE ACTION OF CORTISONE ACETATE ON ISOLATED CARDIAC TISSUE JF - Journal of Pharmacology and Experimental Therapeutics JO - J Pharmacol Exp Ther SP - 168 LP - 175 VL - 128 IS - 2 AU - Ralph D. Tanz AU - James W. Bray AU - Jacqueline H. Hill Y1 - 1960/02/01 UR - http://jpet.aspetjournals.org/content/128/2/168.abstract N2 - The action of cortisone upon the isolated cat papillary muscle and isolated whole heart preparations was investigated. The results show that small doses (1 µg/ml) tend to restore the amplitude of contractions to control levels in the isolated heart preparation, and offer histological protection to papillary muscles. This effect is referred to as a "protective" or "normalizing" action. The addition of "toxic" doses of cortisone (40 µg/ml), often resulted in abnormal papillary muscle contractile patterns about an hour and a half after administration. One of these patterns was the production of a marked augmentation following suprathreshold stimulation. Cursory experiments into the nature of this phenomena implicate the endogenous release of adrenergic mediators. A "toxic" dose of cortisone also brought about a negative inotropic response of both papillary muscle and intact heart preparations. ER -